HER2阳性和三阴性乳腺癌新辅助化疗后选择性避免腋窝手术分期的研究

背景与目的：新辅助化疗（neoadjuvant chemotherapy，NAC）目前已成为局部晚期乳腺癌患者的标准治疗模式。探讨人表皮生长因子受体2（human epidermal growth factor receptor 2，HER2）阳性和三阴性乳腺癌（triple-negative breast cancer，TNBC）患者NAC后选择性避免腋窝手术分期的可行性及可能获益人群。方法：回顾性分析2010年1月—2018年8月山东省肿瘤防治研究院（山东省肿瘤医院）收治的865例行NAC患者的临床病理学资料，其中184例（21.3%）为HER2阳性和TNBC患者，分析其临床病理学特征与NAC后腋窝淋巴结病理学阴性（ypN ₀ ）的相关性。结果：NAC前肿瘤分期、淋巴结分期及Ki-67，NAC后腋窝淋巴结临床阴性（ycN ₀ ）、乳房影像学完全缓解（breast radiologic complete response，brCR）及乳房病理学完全缓解（breast pathologic complete response，bpCR）均与NAC后ypN ₀ 显著相关（P<0.05），其中NAC前临床淋巴结分期（OR=0.363，P<0.001）、bpCR（OR=11.285，P<0.001）及ycN ₀（OR=4.995，P<0.001）是NAC后ypN ₀ 的独立预测因素。cN ₀ →ycN ₀ 组37例，NAC后bpCR、未达bpCR患者ypN ₀ 率分别为100.0%（17/17）、90.0%（18/20）（P=0.178）。cN ₁ →ycN ₀ 组42例，NAC后bpCR、未达bpCR患者ypN ₀ 率分别为95.8%（23/24）、55.6%（10/18）（P<0.001）。NAC后未达bpCR的cN 1 患者腋窝淋巴结残留转移的相对风险是bpCR患者的10.56倍（95% CI：2.720~41.003；P<0.001）。结论：在HER2阳性和TNBC患者中，NAC后bpCR与腋窝淋巴结状态具有高度相关性。NAC后bpCR的cN ₀ 及部分cN ₁ 患者（NAC后降期为ycN ₀ ）腋窝淋巴结残留转移的风险<5%，使其选择性避免腋窝手术分期成为可能。

Selective elimination of axillary surgery staging after neoadjuvant chemotherapy for HER2 positive and triple-negative breast cancer

Background and purpose: Neoadjuvant chemotherapy (NAC) has become the standard treatment mode for locally advanced breast cancer patients. This study aimed to explore the feasibility of selective elimination of axillary surgery staging after NAC in human epidermal growth factor receptor 2 (HER2) positive and triple-negative breast cancer (TNBC) patients, and to assess which patients would acquire greater benefits from it. Methods: From Jan. 2010 to Aug. 2018, 865 patients who underwent surgery after NAC in Shandong Cancer Hospital and Institute were included in this retrospective study to analyze the correlation between clinicopathological characteristics of HER2 positive and TNBC patients and pathologically negative axillary lymph nodes after NAC(ypN ₀ ). Results: Among the 184 (21.3%) HER2 positive and TNBC patients receiving NAC, tumor staging, lymph node staging and Ki-67 before NAC, clinically node-negative (ycN ₀ ), breast radiologic complete response (brCR) and breast pathologic complete response (bpCR) after NAC were correlated with ypN ₀ (P<0.05). Clinical lymph node staging before NAC (OR=0.363, P<0.001), bpCR (OR=11.285, P<0.001) and ycN ₀ (OR=4.995, P<0.001) were the independent predictors of ypN ₀ . Among 37 patients with clinically nodal-negative breast cancer before (cN ₀ ) and after (ycN ₀ ) NAC, 17 of 17 (100.0%) with and 18 of 20 (90.0%) without a bpCR had no evidence of residual nodal disease (P=0.178). Among 42 patients with cN ₁ to ycN ₀ , 23 of 24 (95.8%) with and 10 of 18 (55.6%) without a bpCR had no evidence of residual nodal disease (P<0.001). Patients without a bpCR had a relative risk for nodal residual metastases of 10.56 (95% CI: 2.720-41.003; P<0.001) compared with those with a bpCR in cN ₁ group. Conclusion: In HER2 positive and TNBC patients, bpCR is highly correlated with nodal status after NAC. The risk of axillary lymph nodes residual metastases after NAC in the patients of bpCR with cN ₀ and cN ₁ to ycN ₀ was less than 5%, making it possible to selectively eliminate axillary surgery staging.